Computer networks of e.g. businesses have several to thousands of users, and concomitantly several to thousands of workstations or other information access points (IAPs). Information Technology (IT) professionals typically are tasked with maintaining and enhancing the operability of each computer on the system. Traditionally, network performance has been assessed by measuring resources which are common across the network, such as network load, application response time and server activity. From these measurements, the service level of end users has been inferred. These traditional, server-centric level-of-service measures may still not given an accurate picture of IAP operability as experienced by individual users.